The spectrum of β-thalassemia mutations in Baghdad, Central Iraq.

While previous studies from Iraq have focused on β-thalassemia (β-thal) mutations in the northern part of the country, inhabited mainly by Kurds, no study of significance has looked at these mutations in central or southern Iraq, which is inhabited by the Arab majority. For the latter purpose this study was initiated and 103 β-thal carriers from Baghdad at the center of the country were investigated using multiplex polymerase chain reaction (PCR) and reverse hybridization followed by sequencing. The results revealed that a total of 17 mutations were implicated, six of which, IVS-I-110 (G>A), IVS-II-1 (G>A), IVS-I-5 (G>C), codons 8/9 (+G), IVS-I-I (G>A) and codon 44 (-C), constituted 78.0% of the mutations characterized. Among the 17 mutations identified, six are reported for the first time from Iraq and include: IVS-I, 25 bp deletion, IVS-II-848 (C>A), -28 (A>C), IVS-I-130 (G>C), IVS-I-128 (T>G) and codons 41/42 (-TTCT). The findings of the current study clearly illustrate the genetic heterogeneity of the population of central Iraq, as demonstrated by the presence of a combination of Mediterranean, Asian Indian, Kurdish, Iranian, Egyptian, Saudi Arabian and Turkish mutations that is reflective of the historical background of this part of the country.